Latch for interchangeable lens mounts



June 15, 1937. v. v. COLAIACE 2,083,637

I LATCH FOR INTERCHANGEABLE LENS MOUNTS Filed Feb. 4, 1936 Patented JuneK 15, 1937 UNITED STATES m'ron i on mancnanomnns LENS MOUNTS Victor V.Colaiace, Rochester, N. Y., assignor, by

mesne assignments, to Eastman Kodak Company, Jersey City, N. J., acorporation of New Jersey Application February 4, 1936, Serial No.62,322

6 Claim.

This invention relates to photography and more particularly to a latchfor releasing a removable lens mount Irom a locked position onphotographic apparatus, such as cameras or projectors. v One object ofmy invention is to provide a latch member which is permanently fastenedto a removable lens mount so that it can be easily operated to eflect arelease of the locking means between the lens mount and the photographicapparatus on which it is mounted. Another ob- Ject is to provide a latchwhich is simple and emcient. And still another object is to provide alatch of small and pleasing contour so that when it is permanently fixedto a removable lens mount it will add a finished and neat appearancethereto.

My latch is adapted to provide a lock releasing means when used inconjunction with removable lens mounts which arelocked in position on acamera by having a spring pressed plunger, which extends through saidcamera well, adapted to engage an aperture in the base plate oi. thelens mount to prevent any relative rotation of the two with respect toone another. The latch, as shown, consists 01' a casing which is mountedon the base plate in covering position relative to the aperture therein,and a suitably milled block having a cam face is slidably mounted insaid casing and normally spring pressed to a position wherein the springpressed plunger is allowed to enter the aperture in the base plate andextend into the casing covering said aperture. Then, by sliding the camfaced block against a spring pressing means the spring pressed plungeris cemmed out 01' the aperture and the lens mount is unlocked forremoval fromthe camera.

The novel features that I consider characteristic of my invention areset forth with particularity in the appended claims. The inventionitself, however, both as to its organization and its method ofoperation, together with additional objects and advantages thereof, willbest be understood from the following description of specificembodiments when read in connection with the following drawing in which;

Figure 1 is a perspective view showing parts of a. camera equipped withanobjective carried by a removable mount having a latch constructed inaccordance with and embodying a preferred iorm of my invention,

Figure 2 is a perspective view of a portion of the front camera wall anda portion of the lens lens mount in said camera wall,

Figure 3 is an enlarged transverse section of Y the latch and camerawall showing the lens mount in a locked position. a

' Figure 4 is a front elevation of the base plat and associated latch asa unit separate from the lens mount,

Figure'5 is a rear elevation of the base plate showing the aperturetherein.

Like reference characters refer to corresponding parts in the drawing.

As illustrated camera I is provided with a movable door 2 through whicha film can be loaded into or removed from said camera. Front wall 3 ofthe camera I has .an aperture 4 behind which is situated a seating ring5 having a pair of recesses 6 cut into the face thereof, said reoessesbeing diametrically opposite one another.

The periphery of the aperture i is provided with a pair of suitableslots 1 in axial alignment with .the recesses 6 in the seating ring 5,said slots being of a size to accommodate the lugs 8 on the rear lenselement 9 of the lens mount iii and allow said lugs 8 to be seated inthe recesses 6. Inasmuch as the slots '1 are narrower than the recesses6, the lens mount i0 is held in place on the camera front 3 by aligningthe lugs 8 ,on the rear lens element 9 with slots 1,-seating said lugsin the recesses 6, and giving the lens mount a partial rotation to throwsaid lugs 8 out 01' alignment with the slots 1.

In order to properly position the lens mount so that the lens will be inproper focus with the plane of the film strip moving through the gate ofthe camera when said lens mount is inserted in the seating ring 5, theresilient member I! is fixed to the seating ring 5 in such a way thatitacts as an abutting means for the lugs 8 on the lens mount when the lugsare rotated in the recesses 5, and the resilient member I l constantlyforces said lens mount rearwardly, thereby tightly abutting it against adefinitely positioned flange in the seating ring 5, which is not shown.

A plunger i2 extends through an aperture IS in the front wall 3 of thecamera, and is normally spring pressed forward by means 01' a spring i4,one end of which is fastened to the inside of the camera wall, as shownin Figure 3, while the other end passes through a hole in the plunger.Plunger I2 is provided with a collar i5 which is' fixed thereto for thepurpose of limiting the extent to which a plunger can extend through thecamera wall 3.

' A base plate I t is permanently fixed to the removable. lens mount itin any suitable manner. The base plate Ilisprovided with a wing portionI! of suitable dimensions to cover thespring plunger l2 when the lensmount is mounted on the camera. And this wing portion 11 is providedwith an aperture ll through which said sprlngplunger I2 is adapted toextend in order to positively lock the lens mount Ill against rotationwith respect to its mounting means in camera wall I.

A casing I! is mounted on the wing portion ll of the base plate It incovering relation with the aperture ll therein, and within said casing a1 ll suitable block 2! is slidably mounted. The block 20 is normallyforced to the upper end of the casing it by aspring 2|, as shown inFigure 3. And that portion of the block 20 opposite the aperture it,when the block is in the position shown. is 80 provided with a recess 22whose dimensions are such as to permit the plunger i 2 to extend intothe aperture II and into the casing is, in which position the lens mountis positively locked on the camera front against rotation and subse- 85quent removal therefrom.

-'I'he upper portion of the block 2. is made to completely fill casingis so that the face 22 thereof lies fiush with the face of the baseplate. and this portion of the block is connected to the 30 base of therecess 22 by a cam surface 24 which acts to cam the plunger l2 out ofthe aperture is when said block is slid downward against the springpressing means 2|. A sliding of the block 2|, to the releasing position,is accomplished by 35 pressing the button 2| which is fastened to theblock by means of a pin 28 passing therethrough said pin extendingthrough slot 21 in the wall of the casing II. A stopmember 2| is mountedon the inside of the casing II to engage in notch 22 in top of the block20 so that as the block is forced to its raised position by the spring2i it is properlystopped, and the shock of the stopping is taken by thestop member 28 instead of being transmitted across the entire uppersurface of the casing ll.

Inasmuch as-the plunger I2 is only adapted to be cammed out of theaperture It to the point where its tip is flush with the inside wall ofthe base plate, the complete expulsion of said plunger is accomplishedby having the outside edge of the aperture ll chami'ered or rounded. asshown at 22, to act against the rounded end of the .plunger l2 and'completely cam said plunger from engagement with the aperture II as the5 base plate is rotated on-the camera front to effect its removaltherefrom. Chamfering of the aperture It as shown at III, alsofacilitates the admissiomof. the plunger i2 into said aperture when the;lens mount it is positioned on the camera.

This latch means provides a simple and efficient means for releasingthis type of removable lens mount from looking engagement with thecamera as well as giving the lens mount and the locking means thereforeafinished appearance which is lacking when the plunger is merely allowedto extend through an uncovered aperture in the base plate, in whichcase'the expulsion of the plunger has to be eifected by the finger. Theincorporation of this type of latching means also reduces the chance ofaccidentallydepressing the plunger or defacing its contour, in whichcase its proper function might be impaired.

Although I have shown and described certain specific embodiments of myinvention. I am fully aware that many modifications thereof areposaoaaes'r sible. My invention, therefore, is not to be restrictedexcept insofar as necessitated by the prior art and the spirit of theappended claims.

Having thus described my invention, what I declare as new and desire tosecure by Letters 5 Patent of the United- States is:

1. In a lens mounting for photographic cameraathe combination with asupport provided with an opening, a spring pressed member extendingthrough said support adjacent said 10 opening, a'removable lens mountadapted to ex- I tend into, said opening in the support "when mountedthereon, cooperating means on the support adjacent said opening and onthe lens mount whereby the lens mount in one position can be.v insertedinto the. opening and can be locked against removal therefrom upondisplacement from said position. .a base plate on said lens mount andhaving an aperture adapted to receive said spring pressed member in thelocked position of the mount, of a suitable means mounted on said baseplate adjacent said aperture and adapted to expel said spring pressedmember from the aperture prior to'unlocking the lens mount with respectto the support.

2. In a lensmounting, for photographic cameras, the combination with asupport provided with an opening. a spring pressed member extendingthrough said support adjacent said opening, a removable lens mountadapted to extend into said opening in the support when mounted thereon,cooperating means on the support ad- Jacent said opening and on the lensmount whereby the lens mount in one position can be inserted into theopening and can be locked against removal therefrom upon displacementfrom said position, a base plate on said lens mount and having anaperture adapted to receive said spring pressed member in the lockedposition of the mount, of a releasing means movably mounted between twopositions on said base plate over the aperture therein whereby movementof said releasing means into one position expels the spring pressedmember from the aperture.

3. In a lens mounting for photographic cameras, the combination with asupport provided with an opening, a spring pressed plunger ex tendingthrough said support adjacent said opening, a removable lensmountadapted to extend into said opening in the support when mounted thereon,cooperating means on the support ad- Jacent said opening and on the lensmount whereby the lens mount in one position can be in-' serted into theopening and can be locked against removal therefrom upon displacementfrom said position, a base plate on said lens mount and having anaperture adapted to receive said plunger in the locked position of themount, of a releasing means siidably mounted on the base plate over theaperture therein and capable of two positions, one position wherein theplunger is allowed to extend through said apertme, and a second positionwherein the plunger is expelled from the aperture. I

4. In a lens mounting for photographic cam eras, the combination with asupport provided with an opening, a spring pressed plunger ex-' tendingthrough said support adjacent said opening, a removable lens mountadapted to extend into said opening in the support when mountedthereon,cooperating means on the support adja'ent said opening and onthe lens mount whereby the lens mount in one position can be insertedinto the opening and can be locked against removal therefrom upondisplacement from said 7s i'aced member slidably mounted on thebaseplate and adapted in'one position to permit the plunger to enter theaperture in the base plate, and in another position to cam said plungerfrom said aperture.

5. In a lens mounting for photographic cam-- eras, the combination'witha support provided with an opening, a spring pressed plunger extendingthrough said support adjacent said opening, a removable lens mountadapted to extend into said opening in the support when mounted thereon,cooperating means on the support adjacent said opening and on the lensmount whereby the lens mount in one position can be inserted into theopening and can be locked against removal therefrom upon displacementfrom said 6. In a lens mounting for photographic cameras, thecombination with a support provided with an opening, a spring pressedplunger extending through said support adjacent said opening, aremovable lens mount adapted to extend into said opening in the support.when mounted thereon, cooperating means on the support adjacent saidopening, and on the lens mount whereby the lens mount in oneposition canbe prising a casing covering the aperture in the base plate, a cam facedblock slidably mounted in said casing between two positions. a lockingposition wherein the plunger is allowed to extend through the baseplate, and an unlocking position wherein the plunger is cammed out ofthe aperture in the base plate, resilient means normally forcing saidblock to its locking position.

and suitable means connected to the cam faced block and extending to theoutside ofthe casing for sliding the block to cam the plunger from theaperture in the base plate prior to unlocking the lens mount from thesupport.

- VICTOR V. COLAIACE.

